Drought-Induced Forest Decline
#00040
Prolonged and recurring drought is weakening forests globally, depriving trees of the water they need to grow, defend themselves against pests, and survive heatwaves. It is the foundational stress factor behind most forest dieback crises.
Parent issue
#00039 Forest Dieback Crisis
Sustainable Development Goals
Location
global
Description
Trees depend on soil moisture to photosynthesize, grow, and regulate their temperature through transpiration. When drought persists over multiple seasons, trees shut down gas exchange to conserve water, but this also stops growth and cooling. Prolonged stress leads to branch dieback, canopy thinning, and eventually death.
Drought also lowers trees' chemical defenses, making them easy targets for bark beetles, fungi, and other opportunistic pathogens. In many regions, the combination of drought and secondary attackers is far more destructive than either factor alone.
The severity of drought-induced decline varies by region depending on local geology, soil type, groundwater access, and tree species composition. Regional sub-issues below document specific local conditions and invite solutions tailored to each context.